This invention relates generally to a baler for forming cylindrical bales of crop material, commonly referred to as a round baler. More particularly, this invention is directed to improved mounting apparatus for the belt idler rollers on round balers using belts in the formation of bales.
Prior art balers of this type generally have a bale forming chamber defined by an apron comprising an array of side-by-side belts, transverse slats extending between chains, a plurality of bale forming rolls or a combination of these various elements, e.g., bale forming rolls and side-by-side belts. U.S. Pat. No. 5,044,272 issued Sep. 3, 1991 to Richard E. Jennings shows the joint use of rolls and belts to form a chamber.
During field operation of round balers, crop material, such as hay, is picked up from the ground and fed into a fixed or adjustable chamber where it is rolled up to form a compact cylindrical package of hay. While still in the bale forming chamber the formed package is wrapped in its compacted form by net, twine or the like, prior to being ejected as a bale from the baler onto the ground for subsequent handling.
Round balers of the general type mentioned above comprising a chamber defined at least partially by a plurality of side-by-side, longitudinally extending belts supported on a plurality of transverse rollers have encountered problems of varying degree when stray crop material and other debris, such as dirt and dust, finds its way into the mounting bearings for the transverse rollers. These problems become especially acute when the material being baled is damp, and particularly if it is a short cut of grass crop. Field experience has shown that standard bearing seals are not sufficient to prevent the fine random debris from working its way into the bearing cavity. Eventually, if permitted to go uncorrected, serious wear problems may occur culminating in bearing failure. Of particular concern is bearing failure that generates excessive frictional heat which gives rise to the danger of igniting a fire in extremely dry conditions.
A number of known prior attempts to reduce or overcome this problem have been unsuccessful. In this regard, various commercially available metallic shields adapted to be mounted in the vicinity of the bearing cavity have been tried. An example of these shields is the axial ring sold by Ziller and Company of West Germany under the registered trademark NILOS. After continuous use of this type of shield in the baler environment described above the bearing cavity became contaminated with unwanted debris.
In another unsuccessful attempt to maintain the integrity of the bearing cavity a pliable washer was fabricated from a fiber material having the consistency of leather. Here again after continuous use in the field environment described above the seal broke down and unwanted debris entered the bearing cavity with the same detrimental affect on the operation of the roller mounting assembly.
Although previously known shielding arrangements for preventing debris from entering the bearing cavity in round baler roller mounting assemblies have met with varying degrees of success, failure continues to occur. At the heart of the problem is the environment in which these mounting assemblies are being used. Regardless of initial sealing characteristics when the shields are installed, after the rigors of continuous use in dirty and damp conditions unwanted debris works past the prior art shielding devices and ultimately penetrates the bearing seal causing bearing to seize up and fail. Thus, integrity of the debris shield over long periods of use is an important aspect of reliable round baler performance to which the present invention is devoted.